mbx 1.24.0

A build cache for Rust projects
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272

use super::*;
use filetime::FileTime;

const DAY: Duration = Duration::from_secs(24 * 60 * 60);

fn now() -> SystemTime {
    SystemTime::UNIX_EPOCH + Duration::from_secs(1_800_000_000)
}

/// Write `files` below `directory`, then date every file and directory in it
/// `age` before [`now`], as a build that last read them then would leave them.
fn unit(directory: &Path, files: &[&str], age: Duration) {
    for file in files {
        let path = directory.join(file);
        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
        std::fs::write(&path, file.as_bytes()).unwrap();
    }
    let time = FileTime::from_system_time(now() - age);
    let mut pending = vec![directory.to_path_buf()];
    while let Some(next) = pending.pop() {
        for entry in std::fs::read_dir(&next).unwrap().flatten() {
            if entry.file_type().unwrap().is_dir() {
                pending.push(entry.path());
            }
            filetime::set_file_times(entry.path(), time, time).unwrap();
        }
        filetime::set_file_times(&next, time, time).unwrap();
    }
}

fn profile(view: &Path) -> PathBuf {
    let profile = view.join("debug");
    std::fs::create_dir_all(&profile).unwrap();
    std::fs::write(profile.join(".cargo-lock"), b"").unwrap();
    profile
}

const NEW_UNIT: &[&str] = &[
    "fingerprint/lib-widget",
    "fingerprint/lib-widget.json",
    "out/libwidget-0123456789abcdef.rlib",
];

#[test]
fn removes_the_units_no_build_used_within_the_age_limit() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    let stale = profile.join("build/widget/0123456789abcdef");
    let fresh = profile.join("build/widget/fedcba9876543210");
    let lonely = profile.join("build/gadget/0123456789abcdef");
    unit(&stale, NEW_UNIT, 40 * DAY);
    unit(&fresh, NEW_UNIT, 2 * DAY);
    unit(&lonely, NEW_UNIT, 40 * DAY);

    let outcome = prune(view.path(), 30 * DAY, now(), false);

    assert_eq!(outcome.removed_units, 2);
    assert!(outcome.removed_bytes > 0);
    assert!(!stale.exists());
    assert!(fresh.join("out/libwidget-0123456789abcdef.rlib").is_file());
    assert!(
        !profile.join("build/gadget").exists(),
        "a package directory with no units left is removed"
    );
    assert!(
        std::fs::read_dir(&profile)
            .unwrap()
            .flatten()
            .all(|entry| !entry
                .file_name()
                .to_string_lossy()
                .starts_with(REMOVAL_PREFIX)),
        "nothing is left moved aside"
    );
}

#[test]
fn a_read_of_the_fingerprint_keeps_an_old_unit() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    let used = profile.join("build/widget/0123456789abcdef");
    unit(&used, NEW_UNIT, 40 * DAY);
    // A fresh build reads the hash and writes nothing.
    filetime::set_file_atime(
        used.join("fingerprint/lib-widget"),
        FileTime::from_system_time(now() - DAY),
    )
    .unwrap();

    let outcome = prune(view.path(), 30 * DAY, now(), false);

    assert_eq!(outcome, UnitOutcome::default());
    assert!(used.join("out/libwidget-0123456789abcdef.rlib").is_file());
}

#[test]
fn the_age_limit_allows_a_day_for_relatime() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    let unit_directory = profile.join("build/widget/0123456789abcdef");
    unit(&unit_directory, NEW_UNIT, 30 * DAY + DAY / 2);

    assert_eq!(prune(view.path(), 30 * DAY, now(), false).removed_units, 0);
    assert!(unit_directory.exists());
}

#[test]
fn retires_an_unused_pre_1_100_layout_whole() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    unit(
        &profile.join(".fingerprint/widget-0123456789abcdef"),
        &["lib-widget", "lib-widget.json"],
        40 * DAY,
    );
    unit(
        &profile.join(".fingerprint/widget-fedcba9876543210"),
        &["build-script-build-script-build"],
        40 * DAY,
    );
    unit(
        &profile.join("deps"),
        &["libwidget-0123456789abcdef.rlib"],
        40 * DAY,
    );
    unit(
        &profile.join("build/widget-fedcba9876543210"),
        &["build-script-build", "out/generated.rs"],
        40 * DAY,
    );
    let current = profile.join("build/widget/0123456789abcdef");
    unit(&current, NEW_UNIT, DAY);

    let outcome = prune(view.path(), 30 * DAY, now(), false);

    assert_eq!(outcome.removed_units, 2);
    assert!(!profile.join(".fingerprint").exists());
    assert!(!profile.join("deps").exists());
    assert!(!profile.join("build/widget-fedcba9876543210").exists());
    assert!(
        current
            .join("out/libwidget-0123456789abcdef.rlib")
            .is_file()
    );
}

#[test]
fn keeps_a_pre_1_100_layout_any_build_still_uses() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    unit(
        &profile.join(".fingerprint/widget-0123456789abcdef"),
        &["lib-widget"],
        40 * DAY,
    );
    unit(
        &profile.join(".fingerprint/gadget-fedcba9876543210"),
        &["lib-gadget"],
        DAY,
    );
    unit(
        &profile.join("deps"),
        &["libwidget-0123456789abcdef.rlib"],
        40 * DAY,
    );

    assert_eq!(
        prune(view.path(), 30 * DAY, now(), false),
        UnitOutcome::default()
    );
    assert!(
        profile
            .join("deps/libwidget-0123456789abcdef.rlib")
            .is_file()
    );
}

#[test]
fn finds_profiles_below_a_target_triple() {
    let view = tempfile::tempdir().unwrap();
    let cross = profile(&view.path().join("aarch64-unknown-linux-gnu"));
    let stale = cross.join("build/widget/0123456789abcdef");
    unit(&stale, NEW_UNIT, 40 * DAY);

    assert_eq!(prune(view.path(), 30 * DAY, now(), false).removed_units, 1);
    assert!(!stale.exists());
}

#[test]
fn a_dry_run_reports_without_removing() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    let stale = profile.join("build/widget/0123456789abcdef");
    unit(&stale, NEW_UNIT, 40 * DAY);

    let outcome = prune(view.path(), 30 * DAY, now(), true);

    assert_eq!(outcome.removed_units, 1);
    assert!(outcome.removed_bytes > 0);
    assert!(stale.join("out/libwidget-0123456789abcdef.rlib").is_file());
}

#[test]
fn finishes_a_removal_an_interrupted_collection_left() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    let abandoned = profile.join(format!("{REMOVAL_PREFIX}1/0"));
    unit(&abandoned, NEW_UNIT, DAY);

    let outcome = prune(view.path(), 30 * DAY, now(), false);

    assert!(!profile.join(format!("{REMOVAL_PREFIX}1")).exists());
    assert!(
        outcome.removed_bytes > 0,
        "the leftover's bytes were counted in the view's size, so they count as freed"
    );
}

#[test]
fn finishes_a_pre_1_100_layout_an_interrupted_collection_left() {
    let view = tempfile::tempdir().unwrap();
    let profile = profile(view.path());
    // `.fingerprint/` went first; the outputs it vouched for did not follow.
    unit(
        &profile.join("deps"),
        &["libwidget-0123456789abcdef.rlib"],
        DAY,
    );
    unit(
        &profile.join("build/widget-fedcba9876543210"),
        &["build-script-build"],
        DAY,
    );
    let current = profile.join("build/widget/0123456789abcdef");
    unit(&current, NEW_UNIT, DAY);

    let outcome = prune(view.path(), 30 * DAY, now(), false);

    assert!(outcome.removed_bytes > 0);
    assert!(!profile.join("deps").exists());
    assert!(!profile.join("build/widget-fedcba9876543210").exists());
    assert!(
        current
            .join("out/libwidget-0123456789abcdef.rlib")
            .is_file()
    );
}

#[test]
fn finds_an_editors_profile_below_its_own_target_triple() {
    let view = tempfile::tempdir().unwrap();
    let nested = profile(&view.path().join("rust-analyzer/aarch64-unknown-linux-gnu"));
    let stale = nested.join("build/widget/0123456789abcdef");
    unit(&stale, NEW_UNIT, 40 * DAY);

    assert_eq!(prune(view.path(), 30 * DAY, now(), false).removed_units, 1);
    assert!(!stale.exists());
}

#[test]
fn a_directory_outside_any_profile_is_left_alone() {
    let view = tempfile::tempdir().unwrap();
    // No `.cargo-lock`: not a directory Cargo builds in.
    let stray = view.path().join("debug/build/widget/0123456789abcdef");
    unit(&stray, NEW_UNIT, 40 * DAY);

    assert_eq!(
        prune(view.path(), 30 * DAY, now(), false),
        UnitOutcome::default()
    );
    assert!(stray.exists());
}